you aren't just making sounds, your whole body is engaged in the laughter. In fact, there are 15 different muscles in your face alone that participate in laughter. Your respiratory system gets involved as well, which is why you can sometimes find breathing difficult, or even get the hiccups, while laughing. Your epiglottis is vibrating, half-closing over your larynx. This makes it more difficult to breathe. As your air intake ebbs and flows, the relative strength of your laughter will follow suit.

If your struggle for oxygen is strong enough, this will activate your tear ducts. Lastly, the force of laughter causes muscle contractions throughout your body in your limbs, your diaphragm and your back.

The scientists then went on to calculate that just 15 minutes of laughter a day will burn 10 to 40 calories, depending on a person’s weight and the intensity of the laughter. That’s enough to shift between 1 to 2 kg.

The idea that laughter benefits health has been around for many years, possibly because it reduces muscle tension, increases the amount of oxygen in the blood, exercises the heart and produces happy chemicals in the brain called endorphins.